An LED generally exits white light by the following ways: a first way is that providing a blue LED chip and yellow phosphor enclosing the blue LED chip, blue light emitting from the blue LED chip exciting the yellow phosphor; a second way is arranging a red LED chip, a green LED chip and a blue LED chip coupled with a circuit, light from the red LED chip, the green LED chip and the blue LED chip to be mixed to exit a white light. However, in the first way, the white light has a color different between a center and a periphery thereof. In the second way, the red light, the green light and the blue light are generally mixed inadequately.